TL;DR
Security doesn't need a budget. It needs about half an hour. Free tiers of the major tools plus a handful of habits will carry a startup through seed stage: Dependabot, GitHub secret scanning, Let's Encrypt, a .gitignore that actually lists .env, environment variables, and validation on the server.
$0 What every tool in the table below costs
The Free Security Stack
Here's the whole stack. Nothing below costs anything.
| Category | Free Tool | What It Does |
|---|---|---|
| Dependency Scanning | Dependabot | Auto-updates vulnerable packages |
| Secret Scanning | GitHub Secret Scanning | Alerts on exposed credentials |
| HTTPS | Let's Encrypt | Free SSL certificates |
| Password Manager | Bitwarden (free) | Secure credential storage |
| 2FA | Google Authenticator | Two-factor authentication |
| Web Scanning | OWASP ZAP | Find web vulnerabilities |
| Secret Detection | TruffleHog | Scan git history for secrets |
| Security Headers | Mozilla Observatory | Check security headers |
Free Practices That Matter Most
Environment Variables ($0)
Never hardcode a secret. API keys, database passwords, anything you would not paste into a public issue: it goes in an environment variable. Every hosting platform supports them, and most will import a .env file for you.
Proper .gitignore ($0)
One line. That's the whole control. List .env and anything holding a credential before your first commit. Prising a secret back out of git history afterwards is painful, and you have to rotate the key anyway.
Input Validation ($0)
Validate on the server, not just in the form. Client-side checks are a UX feature; an attacker skips them by posting to your API directly. Server-side validation shuts down most injection attacks for the cost of an afternoon.
Parameterized Queries ($0)
Use parameterized queries rather than gluing strings together. It ends SQL injection outright, it costs nothing at runtime, and it's usually the shorter code.
HTTPS Everywhere ($0)
Let's Encrypt hands out free certificates and most hosts provision them automatically, so this is often already done. Check anyway. An app you deployed eighteen months ago on a custom domain is where an expired certificate hides.
Key insight: The effective measures are the free ones. A paid scanner pointed at code with hardcoded credentials in it will find the hardcoded credentials and change nothing about why they got there.
Free Tool Deep Dive
Dependabot (GitHub)
- Opens a pull request for you when a dependency has a known advisory
- Free on every GitHub repo, public or private
- Works from the GitHub Advisory Database, so coverage is whatever has been publicly reported
- Set it up once and forget it exists
GitHub Secret Scanning
- Scans commits for accidentally exposed credentials
- Free for public repos, included in Teams/Enterprise
- Integrates with 100+ service providers
- Alerts you before the bots crawling GitHub's public event feed find the key
OWASP ZAP
- Open-source web application scanner
- Finds XSS, SQL injection, and common vulnerabilities
- Can run automated scans in CI/CD
- Active community and regular updates
Free Tier Limitations
They do have ceilings. Here is where each one stops:
| Tool | Free Tier Limit | When to Upgrade |
|---|---|---|
| Snyk | 200 tests/month | Large monorepos or many projects |
| GitGuardian | 25 developers | Team grows beyond 25 |
| Bitwarden | 2 users sharing | Team collaboration needed |
| GitHub Secret Scanning | Public repos only | Private repos on free plan |
When to pay: When a limit is actually blocking you, when a customer asks for compliance documentation, or when you start handling regulated data. Having raised money is not by itself a reason.
Setting Up Your Free Security Stack
Can startups have good security with no budget?
Yes. The measures that matter most cost nothing: secure coding habits, secrets kept out of the repo, HTTPS, and validation on the server. Free tiers cover the rest for a small team.
What free security tools should every startup use?
Dependabot and GitHub secret scanning, both free and both a checkbox. Let's Encrypt for HTTPS, Bitwarden's free tier for shared passwords, and OWASP ZAP to scan the running app.
When should startups start paying for security tools?
When a free tier limit starts blocking work, when someone asks you for compliance documentation, or when you take on regulated data. Funding on its own is not a reason.
Further Reading
Half an hour of setup beats any of the bills these posts describe.
Free Security Scanning
Our free tier catches vulnerabilities before they cost you money.